Coil points sparking

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OhioLeadfoot
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Coil points sparking

Post by OhioLeadfoot » Mon Dec 06, 2021 8:41 am

I purchased a single new coil recently and put it into the number one piston position in the box to help set the timing. I'm noticing as I set the timing at ATDC the points on the coil are sparking, as well as the typical buzzing of the points. Is there something wrong with the new coil to be arcing a spark at the coil points?


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Re: Coil points sparking

Post by Moxie26 » Mon Dec 06, 2021 8:49 am

Revert back to the one you purchased the coil, ask him why it's sparking so much and to what he calibrated the coil .

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OhioLeadfoot
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Re: Coil points sparking

Post by OhioLeadfoot » Mon Dec 06, 2021 8:56 am

The new coil is from Snyder's...their new wood boxed version.

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Re: Coil points sparking

Post by Humblej » Mon Dec 06, 2021 9:01 am

Sparking is what points do when the coil is energized, it is normal. A coil making the buzzing sound is the result of the points rapidly opening and closing, and when the points open and close they spark. When the engine is running the coil is energized for a brief moment, but while you are setting up your timing you are sitting on a buzzing coil for a long period. Sparking is what wears out the points so do not let a coil buzz longer than you need.

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OhioLeadfoot
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Re: Coil points sparking

Post by OhioLeadfoot » Mon Dec 06, 2021 9:14 am

The three older coils don't spark....they buzz, but no sign of sparking like this new coil does. Last night it was a nice night to work around here, the spark coming off of the top of the new coil was significant! Could it be since I didn't have the spark plug attached to the coil, the energy was released at the points instead of down the line at the plug?


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Re: Coil points sparking

Post by greenacres36 » Mon Dec 06, 2021 9:24 am

I bought some brand new wood box coils from a vendor about a year ago. I cannot remember which one. They never worked quite right when I opened them up I found they had puny little capacitors in them. I can’t remember the value but I replaced the capacitors and three out of the four coils pass the ECCT. One of them will not.

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Re: Coil points sparking

Post by Humblej » Mon Dec 06, 2021 9:30 am

I always have a spark plug in the equation when I set my timing.


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Re: Coil points sparking

Post by TXGOAT2 » Mon Dec 06, 2021 9:38 am

I would attach a good spark plug gapped to .025 and see if that reduces the arcing. Be sure the plug is well-grounded to the engine. Avoid operating any coil with the secondary open. It's best to always have a discharge path for the high voltage. A good way to do this is to provide a spark plug that is well-grounded and gapped to the correct gap for the system you're working on. Avoid grounding the high voltage directly, also.


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Re: Coil points sparking

Post by Scott_Conger » Mon Dec 06, 2021 9:39 am

Never, ever let a coil "buzz" without a plug attached, unless you need another burned out coil for your collection.
Scott Conger

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Re: Coil points sparking

Post by OhioLeadfoot » Mon Dec 06, 2021 9:51 am

Thanks for the replies fellows!

I bought this '22 T at an estate auction, which from the looks of things hadn't been run in years. The magneto doesn't seem to work so my only hope of getting it to run is with the 6V side. I had it running for a short time.....enough to see the generator was producing 7 volts, but the backfiring was terrific! Rebuilt the carburetor, and put in a new commutator; loom wiring. I've cleaned the head due to a buildup of carbon and have found issues with the valves not being uniform in their lash. A couple at .012", up to .030"....I'm replacing springs and whatever else necessary to get the valves timed. When I first checked compression, two cylinders were just over 50lbs, two are barely 40lbs. I'm hoping the valve job will do the trick.

So, the coil business isn't the only thing I'm dealing with. But, getting your advice on this one thing is important.


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Re: Coil points sparking

Post by TXGOAT2 » Mon Dec 06, 2021 10:00 am

Backfiring could be late timing, sticky valves, or a lean mixture, or any combination of the above. A running problem does not always indicate a need for repair or replacement. Often as not, cleaning and adjustment will get good results. Compression can vary in an engine that that has been idle for a long time due to sticky rings or valves. 40-50 psi is on the low side, but the engine ought to run OK if the ignition, valves, and carburetion are working reasonabley well. Sticky rings and valves will often respond well to changing the oil and running the engine at moderate speeds and loads for a few hundred miles. Be sure it's broke before you fix it. (Cheaper thataway) There are some easy checks that can determine if the magneto is completely bad or if it is a minor issue like poor contact at the magneto output terminal or at the ignition switch/wiring.


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Re: Coil points sparking

Post by Scott_Conger » Mon Dec 06, 2021 10:05 am

You may still have solid lifters and a worn cam, so varying valve gaps come with the territory.

Don't be in a hurry to do a valve job. While not well "balanced" for compression, it is well within the range that the car will run. Once the car is driveable, run it for 6 months or so and you may find the compression comes up and balances out nicely once the rings are free again.

As a new T owner, GO SLOW with the improvements and tearing things off

Do MTFCAxxxxxxxx searches on subjects like band replacement, driving within the limits of your brakes, and nevernevernever try to take the starter out without first removing the bendix.

Welcome to the affliction
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Re: Coil points sparking

Post by R.V.Anderson » Mon Dec 06, 2021 10:20 am

At the points, there is sparking and then there is sparking. A small amount of it is normal, but a heavy, fat blue spark at the points, with little or none at the plug, means an open condenser. Thin sparks that shoot sideways for a distance means loose contacts. Close examination while nudging the contacts with a small screwdriver will reveal this.


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Re: Coil points sparking

Post by Ron Patterson » Mon Dec 06, 2021 11:35 am

Leander
Sounds to me like one of the newly made BXXXX Cp. coils made in Mexico. Many contain Metalized Mylar capacitors which are incorrect type and exhibit excessive arching at the contact points. If so, will fail quickly.
Get your money back and order a rebuilt coil from Lang's Old Car Parts.
Ron Patterson


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Re: Coil points sparking

Post by Art M » Mon Dec 06, 2021 1:48 pm

I have noticed that if the spark at the coil points is yellow looking, the capacitor in the coil is probably defective.
Capacitor testing meter is readily available on the internet for a maybe 20 bucks. My kids bought my one about 4 years ago so I am not sure exact price.
I check the capacitor and current draw on each coil at the start of each touring season.

Art Mirtes


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Re: Coil points sparking

Post by J1MGOLDEN » Mon Dec 06, 2021 2:06 pm

Your coil will operate for a short period with no capacitor at all.

You will see lots of sparks then!

Open the points with a small insulator and measure the capacitor size.

You will be surprised to note it is very likely only 20 % of the Ford recommended size.

The same size that was used with cars up through the 1980 era or later with points in the distributor.


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Re: Coil points sparking

Post by MichaelPawelek » Mon Dec 06, 2021 7:38 pm

Here is a photo of the new coils Snyder’s is selling with the capacitors that do not pass the test on my ECCT. Will be soldering in the correct capacitors later on this week. Unfortunately I have had them too long to return…..
Image

The orange capacitor shown below is the correct item to use…
Image


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Re: Coil points sparking

Post by speedytinc » Tue Dec 07, 2021 8:25 am

When you get the correct caps in, POT THEM. Leaving them unpotted invites connection failures from vibration.

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Re: Coil points sparking

Post by OhioLeadfoot » Tue Dec 07, 2021 11:53 am

Just to see what was in the new wood box coil I purchased; I opened the case......it looks exactly like the photo MichaelPawelek posted. The same yellow capacitor with markings of 684K, 630V.

Image
Image

Forgive me if I don't understand how the markings correlate to actual capacitor performance....I just don't know, outside of the 630V is probably the maximum voltage the capacitor can stand. Is this the poor capacitor to use for a Model T coil?

Ron, when you say "Sounds to me like one of the newly made BXXXX Cp. coils made in Mexico. Many contain Metalized Mylar capacitors....." Is this what you're talking about?


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Re: Coil points sparking

Post by MichaelPawelek » Tue Dec 07, 2021 12:22 pm

This morning I cut the yellow capacitors out of the 4 new coils that tested bad, soldered in the correct orange ones, then tested on my ECCT and they all registered “excellent”.

I find it really odd that Snyder’s sells these new coils with incorrect capacitors yet they sell the correct capacitors individually. Go figure…..

Almost ready for re-potting…
Image
Last edited by MichaelPawelek on Tue Dec 07, 2021 1:03 pm, edited 1 time in total.


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Re: Coil points sparking

Post by Tim Moore » Tue Dec 07, 2021 12:31 pm

When you secure the new component I strongly advise you do not use expanding foam. I have seen this done and coils can swell and no longer fit in the coil box.

Tim Moore

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Re: Coil points sparking

Post by OhioLeadfoot » Tue Dec 07, 2021 12:37 pm

MichaelPawelek wrote:
Tue Dec 07, 2021 12:22 pm
This morning I cut the yellow capacitors out of the 4 new coils that tested bad, soldered in the correct orange ones, then tested on my ECCT and they all registered “excellent”.

I find it really odd that Snyder’s sells these new coils with incorrect capacitors yet they sell the correct capacitors individually. Go figure…..
I was wondering the same thing!?! I've not called them to see if they would refund me after the expense of mailing it back (although they say no electronic returns), but their price of a correct capacitor beats the return shipping charge, even IF they would refund my purchase price. I think I'll follow through in boxing up the older coils and have Lang's or someone else provide good quality rebuilt ones.

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OhioLeadfoot
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Re: Coil points sparking

Post by OhioLeadfoot » Tue Dec 07, 2021 12:40 pm

Tim Moore wrote:
Tue Dec 07, 2021 12:31 pm
When you secure the new component I strongly advise you do not use expanding foam. I have seen this done and coils can swell and no longer fit in the coil box.

Tim Moore
So the tar works better......where do you get it?


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Re: Coil points sparking

Post by MichaelPawelek » Tue Dec 07, 2021 1:05 pm

OhioLeadfoot wrote:
Tue Dec 07, 2021 12:37 pm
MichaelPawelek wrote:
Tue Dec 07, 2021 12:22 pm
This morning I cut the yellow capacitors out of the 4 new coils that tested bad, soldered in the correct orange ones, then tested on my ECCT and they all registered “excellent”.

I find it really odd that Snyder’s sells these new coils with incorrect capacitors yet they sell the correct capacitors individually. Go figure…..

I was wondering the same thing!?! I've not called them to see if they would refund me after the expense of mailing it back (although they say no electronic returns), but their price of a correct capacitor beats the return shipping charge, even IF they would refund my purchase price. I think I'll follow through in boxing up the older coils and have Lang's or someone else provide good quality rebuilt ones.
Brent Mize is a member here and will also do a great job for you.
https://www.coildoctor.com/

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OhioLeadfoot
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Re: Coil points sparking

Post by OhioLeadfoot » Wed Dec 08, 2021 5:27 pm

Just a FYI, Snyder's is sending me another new coil in exchange for the first one received. I doubt if it's a better quality unit, but who knows? So, thanks to them. I've also sent off my 4 older coils to Brent Mize for rebuilding. I may still need to use that new coil IF one of the old ones is found to be unbuildable (all 4 boxes show signs of being opened previously).

Thanks to all who replied, I appreciate it very much!


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Re: Coil points sparking

Post by MichaelPawelek » Wed Dec 08, 2021 6:29 pm

When you talked to Snyder’s was the capacitor size discussed?


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Re: Coil points sparking

Post by speedytinc » Wed Dec 08, 2021 7:02 pm

OhioLeadfoot wrote:
Wed Dec 08, 2021 5:27 pm
Just a FYI, Snyder's is sending me another new coil in exchange for the first one received. I doubt if it's a better quality unit, but who knows? So, thanks to them. I've also sent off my 4 older coils to Brent Mize for rebuilding. I may still need to use that new coil IF one of the old ones is found to be unbuildable (all 4 boxes show signs of being opened previously).

Thanks to all who replied, I appreciate it very much!
Its good practice to do 5 @ a time. Carry #5 as a spare.

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OhioLeadfoot
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Re: Coil points sparking

Post by OhioLeadfoot » Sun Dec 12, 2021 12:12 pm

MichaelPawelek wrote:
Wed Dec 08, 2021 6:29 pm
When you talked to Snyder’s was the capacitor size discussed?
The gal acted like she didn't know there was a difference. I've since received the replacement coil from them....it has the same 684K 630V yellow capacitor. I've taken the liberty to replace this yellow capacitor with one of their orange 474K 400V ones. I'll need to have this one checked for usability as a spare.

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Re: Coil points sparking

Post by DanTreace » Sun Dec 12, 2021 1:51 pm

Its good practice to do 5 @ a time. Carry #5 as a spare.
And of course us magneto/trembler coil guys keep that # 5 spare on hand not only for personal breakdowns.......but also for our T friends on tour that are running dizzy disturbotors, when their single coil goes bad....we can help :lol:




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Re: Coil points sparking

Post by speedytinc » Sun Dec 12, 2021 2:46 pm

DanTreace wrote:
Sun Dec 12, 2021 1:51 pm
Its good practice to do 5 @ a time. Carry #5 as a spare.
And of course us magneto/trembler coil guys keep that # 5 spare on hand not only for personal breakdowns.......but also for our T friends on tour that are running dizzy disturbotors, when their single coil goes bad....we can help :lol:

Neat pix. You nice guys carry a soldering iron also?
The smarter dizzy guys carry 1 extra coil also. The equivalent of 4!



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